platform_bionic/libc/tzcode/strptime.c
Elliott Hughes a1fb15bb67 strptime: support everything that strftime supports.
Our strptime was missing `%F`, `%G`, `%g`, `%P`, `%u`, `%V`, and
`%v`. Most of these are already supported upstream (and I've just pulled
their current implementation), but some aren't. We're horribly out of
sync anyway, so I'll upstream the missing pieces and then try to get us
back in sync later.

Test: new tests, but originally found by toybox trying to use %F
Change-Id: Ib1a10801a7a3b9c9189440c3b300109bde535fd9
2019-03-26 19:07:40 -07:00

497 lines
15 KiB
C

/* $OpenBSD: strptime.c,v 1.11 2005/08/08 08:05:38 espie Exp $ */
/* $NetBSD: strptime.c,v 1.12 1998/01/20 21:39:40 mycroft Exp $ */
/*-
* Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code was contributed to The NetBSD Foundation by Klaus Klein.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
//#include <sys/localedef.h>
#include <ctype.h>
#include <errno.h>
#include <locale.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "tzfile.h"
static const struct {
const char *abday[7];
const char *day[7];
const char *abmon[12];
const char *mon[12];
const char *am_pm[2];
const char *d_t_fmt;
const char *d_fmt;
const char *t_fmt;
const char *t_fmt_ampm;
} _DefaultTimeLocale = {
{
"Sun","Mon","Tue","Wed","Thu","Fri","Sat",
},
{
"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday",
"Friday", "Saturday"
},
{
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
},
{
"January", "February", "March", "April", "May", "June", "July",
"August", "September", "October", "November", "December"
},
{
"AM", "PM"
},
"%a %b %d %H:%M:%S %Y",
"%m/%d/%y",
"%H:%M:%S",
"%I:%M:%S %p"
};
#define _ctloc(x) (_DefaultTimeLocale.x)
/*
* We do not implement alternate representations. However, we always
* check whether a given modifier is allowed for a certain conversion.
*/
#define _ALT_E 0x01
#define _ALT_O 0x02
#define _LEGAL_ALT(x) { if (alt_format & ~(x)) return (0); }
struct century_relyear {
int century;
int relyear;
};
static int _conv_num(const unsigned char **, int *, int, int);
static unsigned char *_strptime(const unsigned char *, const char *, struct tm *,
struct century_relyear *);
char *
strptime(const char *buf, const char *fmt, struct tm *tm)
{
struct century_relyear cr;
cr.century = TM_YEAR_BASE;
cr.relyear = -1;
return (char*)(_strptime((const unsigned char*)buf, fmt, tm, &cr));
}
static unsigned char *
_strptime(const unsigned char *buf, const char *fmt, struct tm *tm, struct century_relyear *cr)
{
unsigned char c;
const unsigned char *bp;
size_t len = 0;
int alt_format, i;
bp = (unsigned char *)buf;
while ((c = *fmt) != '\0') {
/* Clear `alternate' modifier prior to new conversion. */
alt_format = 0;
/* Eat up white-space. */
if (isspace(c)) {
while (isspace(*bp))
bp++;
fmt++;
continue;
}
if ((c = *fmt++) != '%')
goto literal;
again: switch (c = *fmt++) {
case '%': /* "%%" is converted to "%". */
literal:
if (c != *bp++)
return (NULL);
break;
/*
* "Alternative" modifiers. Just set the appropriate flag
* and start over again.
*/
case 'E': /* "%E?" alternative conversion modifier. */
_LEGAL_ALT(0);
alt_format |= _ALT_E;
goto again;
case 'O': /* "%O?" alternative conversion modifier. */
_LEGAL_ALT(0);
alt_format |= _ALT_O;
goto again;
/*
* "Complex" conversion rules, implemented through recursion.
*/
case 'c': /* Date and time, using the locale's format. */
_LEGAL_ALT(_ALT_E);
if (!(bp = _strptime(bp, _ctloc(d_t_fmt), tm, cr)))
return (NULL);
break;
case 'D': /* The date as "%m/%d/%y". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%m/%d/%y", tm, cr)))
return (NULL);
break;
case 'F': /* The date as "%Y-%m-%d". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%Y-%m-%d", tm, cr)))
return (NULL);
continue;
case 'R': /* The time as "%H:%M". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%H:%M", tm, cr)))
return (NULL);
break;
case 'r': /* The time as "%I:%M:%S %p". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%I:%M:%S %p", tm, cr)))
return (NULL);
break;
case 'T': /* The time as "%H:%M:%S". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%H:%M:%S", tm, cr)))
return (NULL);
break;
case 'v': /* The date as "%e-%b-%Y". */
_LEGAL_ALT(0);
if (!(bp = _strptime(bp, "%e-%b-%Y", tm, cr)))
return (NULL);
break;
case 'X': /* The time, using the locale's format. */
_LEGAL_ALT(_ALT_E);
if (!(bp = _strptime(bp, _ctloc(t_fmt), tm, cr)))
return (NULL);
break;
case 'x': /* The date, using the locale's format. */
_LEGAL_ALT(_ALT_E);
if (!(bp = _strptime(bp, _ctloc(d_fmt), tm, cr)))
return (NULL);
break;
/*
* "Elementary" conversion rules.
*/
case 'A': /* The day of week, using the locale's form. */
case 'a':
_LEGAL_ALT(0);
for (i = 0; i < 7; i++) {
/* Full name. */
len = strlen(_ctloc(day[i]));
if (strncasecmp(_ctloc(day[i]), (const char*)bp, len) == 0)
break;
/* Abbreviated name. */
len = strlen(_ctloc(abday[i]));
if (strncasecmp(_ctloc(abday[i]), (const char*)bp, len) == 0)
break;
}
/* Nothing matched. */
if (i == 7)
return (NULL);
tm->tm_wday = i;
bp += len;
break;
case 'B': /* The month, using the locale's form. */
case 'b':
case 'h':
_LEGAL_ALT(0);
for (i = 0; i < 12; i++) {
/* Full name. */
len = strlen(_ctloc(mon[i]));
if (strncasecmp(_ctloc(mon[i]), (const char*)bp, len) == 0)
break;
/* Abbreviated name. */
len = strlen(_ctloc(abmon[i]));
if (strncasecmp(_ctloc(abmon[i]), (const char*)bp, len) == 0)
break;
}
/* Nothing matched. */
if (i == 12)
return (NULL);
tm->tm_mon = i;
bp += len;
break;
case 'C': /* The century number. */
_LEGAL_ALT(_ALT_E);
if (!(_conv_num(&bp, &i, 0, 99)))
return (NULL);
cr->century = i * 100;
break;
case 'd': /* The day of month. */
case 'e':
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_mday, 1, 31)))
return (NULL);
break;
case 'k': /* The hour (24-hour clock representation). */
_LEGAL_ALT(0);
/* FALLTHROUGH */
case 'H':
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_hour, 0, 23)))
return (NULL);
break;
case 'l': /* The hour (12-hour clock representation). */
_LEGAL_ALT(0);
/* FALLTHROUGH */
case 'I':
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_hour, 1, 12)))
return (NULL);
break;
case 'j': /* The day of year. */
_LEGAL_ALT(0);
if (!(_conv_num(&bp, &tm->tm_yday, 1, 366)))
return (NULL);
tm->tm_yday--;
break;
case 'M': /* The minute. */
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_min, 0, 59)))
return (NULL);
break;
case 'm': /* The month. */
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_mon, 1, 12)))
return (NULL);
tm->tm_mon--;
break;
case 'P':
case 'p': /* The locale's equivalent of AM/PM. */
_LEGAL_ALT(0);
/* AM? */
len = strlen(_ctloc(am_pm[0]));
if (strncasecmp(_ctloc(am_pm[0]), (const char*)bp, len) == 0) {
if (tm->tm_hour > 12) /* i.e., 13:00 AM ?! */
return (NULL);
else if (tm->tm_hour == 12)
tm->tm_hour = 0;
bp += len;
break;
}
/* PM? */
len = strlen(_ctloc(am_pm[1]));
if (strncasecmp(_ctloc(am_pm[1]), (const char*)bp, len) == 0) {
if (tm->tm_hour > 12) /* i.e., 13:00 PM ?! */
return (NULL);
else if (tm->tm_hour < 12)
tm->tm_hour += 12;
bp += len;
break;
}
/* Nothing matched. */
return (NULL);
case 'S': /* The seconds. */
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_sec, 0, 61)))
return (NULL);
break;
case 's':
{
// Android addition, based on FreeBSD's implementation.
int saved_errno = errno;
errno = 0;
const unsigned char* old_bp = bp;
long n = strtol((const char*) bp, (char**) &bp, 10);
time_t t = n;
if (bp == old_bp || errno == ERANGE || ((long) t) != n) {
errno = saved_errno;
return NULL;
}
errno = saved_errno;
if (localtime_r(&t, tm) == NULL) return NULL;
}
break;
case 'U': /* The week of year, beginning on sunday. */
case 'W': /* The week of year, beginning on monday. */
_LEGAL_ALT(_ALT_O);
/*
* XXX This is bogus, as we can not assume any valid
* information present in the tm structure at this
* point to calculate a real value, so just check the
* range for now.
*/
if (!(_conv_num(&bp, &i, 0, 53)))
return (NULL);
break;
case 'w': /* The day of week, beginning on sunday. */
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &tm->tm_wday, 0, 6)))
return (NULL);
break;
case 'u': /* The day of week, monday = 1. */
_LEGAL_ALT(_ALT_O);
if (!(_conv_num(&bp, &i, 1, 7)))
return (NULL);
tm->tm_wday = i % 7;
continue;
case 'g': /* The year corresponding to the ISO week
* number but without the century.
*/
if (!(_conv_num(&bp, &i, 0, 99)))
return (NULL);
continue;
case 'G': /* The year corresponding to the ISO week
* number with century.
*/
do
bp++;
while (isdigit(*bp));
continue;
case 'V': /* The ISO 8601:1988 week number as decimal */
if (!(_conv_num(&bp, &i, 0, 53)))
return (NULL);
continue;
case 'Y': /* The year. */
_LEGAL_ALT(_ALT_E);
if (!(_conv_num(&bp, &i, 0, 9999)))
return (NULL);
cr->relyear = -1;
tm->tm_year = i - TM_YEAR_BASE;
break;
case 'y': /* The year within the century (2 digits). */
_LEGAL_ALT(_ALT_E | _ALT_O);
if (!(_conv_num(&bp, &cr->relyear, 0, 99)))
return (NULL);
break;
/*
* Miscellaneous conversions.
*/
case 'n': /* Any kind of white-space. */
case 't':
_LEGAL_ALT(0);
while (isspace(*bp))
bp++;
break;
default: /* Unknown/unsupported conversion. */
return (NULL);
}
}
/*
* We need to evaluate the two digit year spec (%y)
* last as we can get a century spec (%C) at any time.
*/
if (cr->relyear != -1) {
if (cr->century == TM_YEAR_BASE) {
if (cr->relyear <= 68)
tm->tm_year = cr->relyear + 2000 - TM_YEAR_BASE;
else
tm->tm_year = cr->relyear + 1900 - TM_YEAR_BASE;
} else {
tm->tm_year = cr->relyear + cr->century - TM_YEAR_BASE;
}
}
return (unsigned char*)bp;
}
static int
_conv_num(const unsigned char **buf, int *dest, int llim, int ulim)
{
int result = 0;
int rulim = ulim;
if (**buf < '0' || **buf > '9')
return (0);
/* we use rulim to break out of the loop when we run out of digits */
do {
result *= 10;
result += *(*buf)++ - '0';
rulim /= 10;
} while ((result * 10 <= ulim) && rulim && **buf >= '0' && **buf <= '9');
if (result < llim || result > ulim)
return (0);
*dest = result;
return (1);
}
char* strptime_l(const char* buf, const char* fmt, struct tm* tm, locale_t l) {
return strptime(buf, fmt, tm);
}